Time Zone Converter
Convert a meeting time or flight time between any two of the world’s time zones, using your browser’s up-to-date daylight saving rules.
Result
Enter your values and select Calculate to see the result.
How to use this calculator
- The date and time default to now, and the “from” zone to your own time zone.
- Choose the zones by region and city, for example Europe / London or Asia / Kolkata.
- The result shows the converted time, both UTC offsets and whether the date changes.
Formula
Each zone’s UTC offset on the chosen date is looked up in the IANA time-zone database built into your browser.
target time = source time − source offset + target offset
Around daylight saving changes, some local times are skipped (clocks go forward) and some happen twice (clocks go back). Skipped times are reported as an error; repeated times use the first occurrence.
Worked example
New York to India in summer
12:00 on 1 July 2024 in New York (UTC−04:00, daylight time) is 16:00 UTC and 21:30 in Kolkata (UTC+05:30).
Crossing the date line
08:00 on 1 January 2024 in Tokyo is 15:00 on 31 December 2023 in Los Angeles.
Assumptions and limitations
- Accuracy depends on your browser’s time-zone data, which is updated with browser and operating-system updates.
- Historical dates before a zone adopted its current rules may be less reliable.
Frequently asked questions
Why is the difference between two cities not always the same?
Countries start and end daylight saving time on different dates, and many never use it, so the gap can change during the year.
What is UTC?
Coordinated Universal Time, the world’s reference time. Time zones are described by their offset from it, such as UTC+01:00.